Argos User’s Manual © 2007-2016 CLS Last updated on June 15, 2016 Table Of Contents 1. Introduction .......................................................................................................................................... 1 2. System components ............................................................................................................................ 2 2.1 Overview ........................................................................................................................................ 2 2.2 Platforms ........................................................................................................................................ 2 2.3 Satellites......................................................................................................................................... 3 2.4 Receiving stations .......................................................................................................................... 5 2.5 Processing centers ........................................................................................................................ 6 2.6 User Services centers across the world ........................................................................................ 6 3. Location calculations ........................................................................................................................... 8 3.1 Overview ........................................................................................................................................ 8 3.2 Argos location principle .................................................................................................................. 8 3.2.1 Physics and Measurement: The Doppler Effect ...................................................................... 8 3.2.2 The positioning algorithm based on Least squares analysis (unchanged since 2007) .......... 9 3.2.3 The positioning algorithm based on Kalman filtering (introduced in 2011) ........................... 10 3.2.4 Error estimation ..................................................................................................................... 11 How to access these parameters ............................................................................................... 12 Column title ................................................................................................................................. 12 Error radius ................................................................................................................................. 12 Semi-major axis .......................................................................................................................... 12 Semi-minor axis .......................................................................................................................... 12 Ellipse orientation ....................................................................................................................... 12 GDOP ......................................................................................................................................... 12 Units ............................................................................................................................................ 12 3.2.5 Altitude estimations ............................................................................................................... 12 3.3 Transmitting GPS data via Argos ................................................................................................ 13 3.4 Location classes .......................................................................................................................... 13 3.5 Choosing a location algorithm ..................................................................................................... 14 3.5.1 Comparative table.............................................................................................................. 14 3.6 Service Plus/Auxiliary Location Processing ............................................................................. 15 4. Data processing ................................................................................................................................. 16 4.1.1 Observation processing vs message processing ..................................................................... 16 4.1.2 Multi-format data processing .................................................................................................... 17 4.1 Overview ...................................................................................................................................... 17 4.1.1 Observation processing vs message processing .................................................................. 17 4.1.2 Multi-format data processing ................................................................................................. 18 4.2 Message format recognition......................................................................................................... 19 4.3 Message segmentation ................................................................................................................ 19 Standard element ........................................................................................................................... 20 Checksum ...................................................................................................................................... 20 Block ............................................................................................................................................... 20 4.4 Data decoding .............................................................................................................................. 20 ii Table Of Contents 4.5 Observation processing ............................................................................................................... 21 4.5.1 Advantages of Observation processing ................................................................................ 22 4.5.2 Distributing observations ....................................................................................................... 22 4.6 Should I choose observations or messages? .............................................................................. 23 4.6.1 Observation processing ........................................................................................................ 24 1. For easy data interpretation ............................................................................................... 24 2. For easy data sharing ........................................................................................................ 24 3. For setting up a monitoring system ................................................................................... 24 4.6.2 Message processing ............................................................................................................. 24 1. For examining the transmission process and verifying platform performance .................. 24 2. For ensuring compatibility with your existing software ...................................................... 24 3. For processing complex formats that change over time .................................................... 24 4. For keeping a raw data archive ......................................................................................... 24 B1 Curve ............................................................................................................................................ 25 B2 Curve ............................................................................................................................................ 25 B3 Curve ............................................................................................................................................ 26 B4 Curve ............................................................................................................................................ 26 5. How to open an Argos account ......................................................................................................... 28 5.1 Obtaining a program .................................................................................................................... 28 5.1.1 Filling out an SUA form and ID number request form ........................................................... 28 5.1.2 Choosing the services (price list) .......................................................................................... 29 5.1.3 Filling out the service contract/order form ............................................................................. 29 5.1.4 Receiving confirmation of program creation ......................................................................... 29 5.2 Managing a program .................................................................................................................... 29 5.2.1 Testing and deploying platforms ........................................................................................... 29 5.2.2 Accessing data ...................................................................................................................... 29 5.2.3 Choosing value-added services ............................................................................................ 30 5.2.4 Settling invoices ...................................................................................................................